Attachment for air-brakes.



F. T. SHAW & J. G. MEADOR, JR. ATTACHNIENT FOR AN? BRAKES.

APFLlCATION FILED AUG.22. 1917.

1,276,976.. Patented Aug. 27, 1918.

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F. T. SHAW & J. G. MEADOR, JR. ATTACHMENT FOR AIR BRAKES.

APPLICATION FILED AUG.22. I917.

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FEED T. SHAW AND JOSEPH G. IVIEADOR, JR., 013 WINCHESTER, MISSISSIPPI.

ATTACHMENT FOR AIR-BRAKES.

Specification of Letters Patent.

Patented Aug. 27, 1918.

Application filed August 22, 1917. Serial No. 187,612.

To all whom it may concern:

Be it known that We, FRED T. SHAW and J osnrrr Gr. MEADOR, J r., citizens of the United States, and residents of Winchester, in the county of Wayne and State of Mississippi, have invented new and useful Improvements in Attachments for Air- Brakes, of which the following is a specification.

Our invention is an improvement in attachments for air brakes, and the invention has for its object to provide means in connection with the relief valve of the air brake cylinder for holding the relief valve open when it has been opened until the piston moves into release position, the releasing of the valve being controlled by the piston.

In the drawings:

Figure 1 is a side View of air brake mechanism provided with the improvement;

Fig. 2 is a front plan view;

Fig. 3 is a longitudinal vertical section;

Fig. 4 is an enlarged sectional view of the release valve.

The present embodiment of the invention is shown in connection with the air drum 1 and the brake cylinder 2 of an air brake system, the piston 3 having the usual rod 1 which is connected with the brake mechanism indicated at 5. This rod runs through the hollow cylinder 6 and a coil spring 7 is arranged between the piston and the outer head 8 of the brake cylinder, the spring acting normally to move the brake piston inwardly.

The usual relief valve 9 is provided, arranged within the casing 10, and normally moved into closed position by a coil spring 11. The usual operating mechanism for the valve is indicated at 12, the said mechanism being arranged to open the valve when the link 13 connected therewith is moved in the proper direction.

A spring-controlled latch, indicated at 14:, is provided for holding the valve open when it has been opened, and this latch is normally pressed into engaging position by a coil spring 15 which encircles the rod or link 16, of which the latch forms a part, between the casing 10 and a stop 17 on the rod or link. As shown in Fig. 4, the latch has a vertical opening through which the valve stem extends, and the latch holds the stem in adj usted position through friction, the spring 15 being stronger than the spring 11. This rod or link moves in a pipe 18 which is supported by the casing and by a bracket 19 on the brake cylinder, and that end of the rod remote from the valve casing is adapted to be engaged by a set screw 20 adjustably connected with a forked lever 21. This lever 21 is pivoted to a bracket 22 on the adjacent end of the pipe 18, and the lower forked end embraces the casing 6, the arms of the fork extending on opposite sides thereof.

A collar 23 is engaged with the outer end of the casing 6, the said collar being stationary on the casing, and this collar is adapted to contact with the arms of the forked lever at the moment when the piston is moving into release position, to cause the lever to operate the rod or link 16 to release the latch 14. The swinging movement of the lever 21 away from the pipe 18 is controlled by a set screw 24: which is threaded through an annular lug 25 at the upper end of the lever 21 and engages the bracket 22 before mentioned.

As is known, when it is desired to release the brake the valve 9 must be opened and held open, and when the car is running this is a proceeding of some danger. With the improvement, however, the opening of the valve controls the latch mechanism to hold the valve open until it is released by therelease of the brakes.

We claim: An attachment for air brakes comprisin in combination with the brake cylinder, the piston, the spring-controlled relief valve, and means for operating the same, of a latch for holding the valve open, a spring controlling the latch, and means operated by the piston at the end of its movement to release position for releasing the latch, said means comprisin a lever pivoted intermediate its ends and having means adjustable with respect thereto for engaging the latch to release the same, and a stop adjustably conpected with the piston for engaging the ever.

FRED'T. SHAW. JOSEPH G. MEADOR, JR.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). G. 

